Evasion of helicity selection rule in chi(c1) -> VV and chi(c2) -> VP via intermediate charmed meson loops

The hadronic decays of chi(c1) -> VV and chi(c2) -> VP are supposed to be suppressed by the helicity selection rule in the perturbative QCD framework. With an effective Lagrangian method, we show that the intermediate charmed meson loops can provide a mechanism for the evasion of the helicity selection rule, and result in sizeable decay branching ratios in some of those channels. The theoretical predictions can be examined by the forthcoming BES-III data in the near future.